Shape Measurements of Lattice Materials from Few X-Ray Radiographs Using the 3D Virtual Image Correlation (3D-VIC) Method

The article introduces the 3D Virtual Image Correlation (3D-VIC) method for measuring the shape of lattice materials using a limited number of X-ray radiographs. This innovative approach bypasses the need for full 3D tomographic reconstruction, which is time-consuming and computationally intensive. The 3D-VIC method leverages virtual projections based on a CAD model and the Beer-Lambert law to register and compare real and virtual projections. The use of Radial Basis Functions (RBF) allows for local shape corrections, ensuring precise and smooth deformations. The method's performance is validated through synthetic radiographs, demonstrating sub-pixel accuracy even with a reduced number of projections and in the presence of image noise. A practical example showcases the method's application on a 3D-printed tetrahedral lattice material, highlighting its ability to detect and measure shape defects accurately.